<!DOCTYPE html>
<html lang="en">
<head>
  <meta charset="UTF-8">
  <meta http-equiv="X-UA-Compatible" content="IE=edge">
  <meta name="viewport" content="width=device-width, initial-scale=1.0">
  <title>Document</title>
</head>
<body>
  <!DOCTYPE html>
  <html lang="en">
  <head>
    <meta charset="UTF-8">
    <meta http-equiv="X-UA-Compatible" content="IE=edge">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <title>Document</title>
  </head>
  <body>
    <script>
      let uname =prompt('请输入用户名')
      let password =prompt('请输入密码')
      while(true){
       
        if(uname === 'admin'  && password === '123456'){
          alert('登录成功')
          break
        }
       uname =prompt('请输入用户名')
       password =prompt('请输入密码')
      }
    </script>
  </body>
  </html>
</body>
</html>